Last Updated: July 23, 2013 10:18pm
Mickelson won the Open two years after finishing runner-up to Darren Clarke at Royal St George's
Phil Mickelson says his win at the Open Championship on Sunday was the greatest of his career - and I completely agree with him.
I did have a sneaky suspicion that Phil, who began the final round five shots behind leader Lee Westwood, could post a score and win the tournament, while he would have been confident after last week's victory at the Scottish Open.
However, the links test has always been the one most alien to Mickelson so to come through like he did on the final day, shooting a 66 and making four birdies in the last six holes, including at the final two, says just about everything.
"Tiger needs a 15th Major to show that he is back to what he was."
After Phil won at Castle Stuart two Sundays back, he said he felt great but insisted that there was still one thing he needed to work on and I think that was his knockdown shots as he played some beauties at Muirfield.
I reckon we could be looking at the new Phil Mickelson, too, as, having replaced his booming game with a more tempered one in the last two weeks, he has gone win-win and become the first man to claim the Scottish Open and the Open Championship back-to-back.
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He has proved to everybody, most importantly himself, that when he plays with a bit more control he actually gives himself more chances to win tournaments and he will now have his eyes on that career Grand Slam.
Phil is three-quarters of the way there, having also won three Masters Green Jackets and a USPGA, so he will be extremely pumped up to win next year's US Open, the only Major Championship to elude him.
Mickelson will have a great chance, too, as the event will be staged at Pinehurst, where he finished second to the late Payne Stewart at the 1999 US Open, while if he carries on this form, he might also make it up to world number one for the first time in his career.
Westwood, however, could find it hard to deal with another missed opportunity in a Major, but he knew all along that despite having a two-shot lead heading into round four he would have to play very well to win - and he didn't.
Lee is known as an exceptional tee-to-green player but he did not make enough fairways at Muirfield on Sunday and instead found the rough and bunkers far too regularly; he wasn't missing his target by miles but he was missing by enough.
Westwood is now the only player in the history of the game to finish in the top three of a Major eight times and not win one, a statistic that on one hand shows how good he is but on the other is extremely frustrating.
Lee's countryman, Ian Poulter, made a dart for the title on Sunday, ending up tied with Westwood and Masters champion Adam Scott in third place at one-over-par, and I was impressed by the way he kept his cool after a trying opening day.
Poulter was angry at Thursday's conditions - something I can understand as some of the pin positions were stupid and the greens got very glassy - but he didn't let that disrupt his golf and if it wasn't for Mickelson and Henrik Stenson, he would have had a shot at winning.
For Tiger Woods, though, the wait for another Major goes on after he finished tied for sixth but it was not a massive surprise he didn't win at Muirfield as even in his best years he never won a Major from behind.
Tiger has returned - he is world number one and has won four times already this year - but he needs a 15th Major to show that he is back to what he was.
I also think he is desperate to silence his critics and please his backers because he certainly cares what they think, that much is clear by the way he likes to always take the positives when he is being interviewed.
Woods could be feeling positive at the end of next year's Open though, as it will be staged at Hoylake and he has done alright there before, hasn't he?
Fred Couples was three-under par for his final round at Muirfield at one stage so the only thing that may scupper him at his Senior Open Championship defence at Royal Birkdale this week is fatigue - but the way he ambles around I don't think that will be an issue and he is my tip at 6/1 with Sky Bet.
Gary Woodland is playing better of late so I will back him to win the RBC Canadian Open in Ontario, while at the Russian Open I will go for 10/1 favourite Simon Dyson; I've seen him put better rounds together than he has of late but he is due a good week.
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